Hi technologyXDA,
I left you a post on XDA-DEV. for you to verify. Based on the FCC TEST REPORT the USA version have 3G on 1900 band. That means it is AT&T comparable. CHCK my sticky post "Manuals & FCC report" for the link.
As for your link to "smart mobiles" those guys just want to attract buyers. Their specs have dozens of errors or inaccuracies. It seems they just got specs from all over and put them together. I wouldn't trust them.
for instance:
3G network: 850 is not used in EU for 3G and 1700 is not in the USA version (see FCC)
Size dimentions: is not accurate
Memory phone book: what they talking about??
Call records: just 30??
400 MB internal memory: 400 is not even a binary number for the CPU, it's 384MB
3G HSDPA 3.6 Mbps: incorrect latest version is 7.2 mbps
Browser: they don't mention Opera 9.5
Motion sensor: HA HA HA HA
Battery Li- Ion: wrong LI-PO
Would you send your money to a place like this?

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